1. Field of the Invention
The present invention relates to an infrared ray reflection pattern-printed transparent sheet.
2. Related Art
In recent years, increased is necessity to convert handwritten characters, pictures, marks and the like to electronic data which can be handled by information processing devices, and in particular, increased is demand to systems in which handwritten informations are input into a computer and the like in real time without passing through a read device such as a scanner and the like.
In order to meet the above situations, proposed are, for example, write type input devices equipped with an input means comprising a pen for handwriting and a face to be written thereon, an input line read means for reading an input line in handwriting input by means of the above input means, an input line converting means for converting the above input line informations into electronic data and an input line data sending means for sending the data converted by the above input line converting means to an information processing device, wherein the input line read means described above is carried out by reading marks which provide position informations formed on the face to be written by means of a sensor mounted in a pen; the above face to be written is a specific paper on which specific dot patterns absorbing an infrared ray are printed as the marks for providing the position informations; and the pen described above is equipped with an infrared ray irradiating part for irradiating the above face to be written with an infrared ray and an infrared ray sensor for detecting infrared ray patterns reflected by the above dot patterns.
In the devices described above, handwritten contents (input lines) can be converted into electronic data, but a direct input target is a dedicated paper, and a separate display device is required in order to display the input line informations converted into the electronic data. Line informations can be visualized on paper by using a pen tip which is charged with graphite or an ink so that lines can be recorded on paper. However, it is not suited to such intuitive and interactive operation as inputting line informations to charts shown on a display by handwriting, and a broader work space in inputting is required. Further, when recording lines on paper, a sheet in which handwriting input has once been finished can not be used, and therefore paper for input which is a consumable good has to be always stored, so that such operation is not suited particularly to mobile uses.
Accordingly, desired are input devices which make it possible to input contents handwritten directly on a screen surface of a display device into an information processing device and which are small-sized and can be produced at a low cost. In order to materialize this, paper which transmits light in a visible region and on which dot patterns are printed can be used as paper which is a means to be written thereon in the write type input device described above, and it is suitably set oppositely to a front face of a display device.
A transparent sheet satisfying the above requirement includes a sheet disclosed in, for example, a patent document 1, which is a transparent sheet mounted on a front face or a front side of a display device and on which marks capable of providing position informations for showing the positions of input lines by an electronic pen for input and the like are printed by using an ink emitting light which can be read by the above input line read means by irradiating with light having a prescribed wavelength. However, the kind of an ink which embodies the above transparent sheet is not described in the patent document 1, and only an idea or a desire of a transparent sheet is described therein. Thus, the examples of a specific transparent sheet are not shown therein.
Further, a coordinate input device prepared by using a transparent member on which a specific ink reflecting light in an infrared region is printed is disclosed in a patent document 2. However, the kind of the ink which materializes the above transparent sheet is not described as well in the patent document 2, and only an idea or a desire thereof is described therein. Thus, the examples of a specific transparent sheet are not shown therein.
On the other hand, when the above transparent sheet is practically used, informations are read, as can be found from FIG. 5 of the patent document 1, by bringing the electronic pen for input into contact with the dot patterns, and therefore the read angle is preferably broadened as much as possible to make it possible to meet various use environments. However, in the existing situation in which transparent sheets standing actual uses have not yet been materialized as described above, transparent sheets which can meet various use environments and which have a broad read angle and are excellent in a read performance are desired to be developed in order to actualize a system in which handwritten informations are input into a computer and the like in real time without passing through a read device such as a scanner and the like.    Patent document 1: Japanese Patent Application Laid-Open No. 256137/2003    Patent document 2: Japanese Patent Application Laid-Open No. 243006/2001